The Importance of Horizontal Mesh Overlap in Open Retromuscular Midline Incisional Hernia Repair: Nationwide Analysis With Long-Term Follow-Up

Abstract Aim Recurrence after open incisional hernia repair remains an issue with long-term rates ranging from 11 to 29%. In open hernia repair it is preferred to place the mesh in the sublay position rather than underlay, however, it is unclear what the optimal mesh overlap is. We sought to determine the importance of this matter. Material and Methods This study was based on a nationwide hernia register allowing for a 100% follow-up from 2007 to 2022. Eligibility criteria were elective incisional hernia surgery, vertical incision, retromuscular mesh placement, and linea alba reconstruction. The 5-year cumulative incidence of reoperation for hernia recurrence was determined. Potential confounders were included in multivariate regression analyses. Results A total of 1539 patients were included. Mean (sd) age was 61.2 (12.4) years and 46.2% were females. The mean horizontal defect size was 8.4 (4.2) cm. Seventy-two (4.7%) patients underwent operative reintervention within 90 days postoperatively, and 112 (7.3%) developed recurrence during a median follow-up of 3.8 (IQR 1.8–6.1) years. Cox regression analysis showed that a mesh width of 10–15 cm significantly decreased the risk of recurrence development compared to both narrower and wider sizes (HR 0.38, CI 0.16–0.90, P = 0.029). Interestingly, in adjusted analysis the fascial defect width was not associated with risk of recurrence. Conclusions For patients undergoing elective open midline retromuscular incisional hernia repair, the size of mesh overlap is important as a golden mean reduces the risk of subsequent hernia recurrence and is more appropriate than both “too little” and “as much as possible”.